Sighting device, in particular a sighting telescope

ABSTRACT

A sighting device is adapted for use with firearms and defining a sighting line, an axis of bore of the firearm and the sighting line forming an acute angle. Means adapted to vary said angle, electric means responsive to the value of the angle and defining a variable output in dependence on the value of said angle are provided. Electric control means define a second variable output in dependence on at least one value causing deviations of the point of impact from the target. Computing means receive the two outputs and generate electric output signals upon divergences between the actual value of the angle and the nominal value of the angle with respect to the at least one value causing a deviation and control means receiving said signals.

United States Patent Vockenhuber 51 Jan. 18, 1972 [54] SIGHTING DEVICE, IN PARTICULAR A FOREIGN PATENTS OR APPLlCATIONS SIGHTING TELESCOPE 1,064,774 4/1967 Great Britain ..33/49 R [72] Inventor: Karl Vockenhuber, Potzleinsdorferstrasse l 18, Vienna 18, Austria Primary Examiner-William D. Martin, Jr. Film? p 18 1 69 AnorneyEmest G. Montague [21] Appl. No.: 859,086 [57] ABSTRACT A sighting device is adapted for use with firearms and defining [30] F i A li fi P i i D t a sighting line, an axis of bore of the firearm and the sighting line forming an acute angle. Means adapted to vary said angle, Sept. 25, AUStl'lfl electric means responsive to the value of the angle and d ing a variable output in dependence on the value of said angle ..33/49 are provided Electric controlmeans defineasecond variable outputin dependence on atleast one value causing deviations [58] Field ofSearch ..33/46 AT, 49, 89/41 R,4l AA of the point of impact from the target Computing means receive the two outputs and generate electric output signals [56] References Cited upon divergences between the actual value of the angle and UNITED STATES PATENTS the nominal value of the angle with respect to the at least one 2 317 419 4/1943 T I l 89/4l R value causing a deviation and control means receiving said ay or et a. Si na1s 2,550,514 4/1951 Alexanderson. ...89/41 R 2 2,570,298 10/ 1951 Wheeler ..33/49 R 25 Claims, 5 Drawing Figures SIGHTING DEVICE, IN PARTICULAR A SIGHTING TELESCOPE The invention relates to a sighting device, in particular to a sighting telescope, provided with means for adjusting the angle between the sighting line and the axis of the bore of a firearm in dependence on correcting values, e.g., the muzzle velocity of the projectile, temperature and angle of the bore with respect to the horizontal line.

Adjusting means of this kind are well known in the art and serve to adjust the sighting line with respect to the ballistic curve of the projectile thus, that they intersect in a predetermined distance. Hand firearms, particularly sporting firearms, usually must be ranged on special projectile types and distances. It has already been suggested to adjust the sighting line with respect to the axis of the bore in dependence on the muzzle velocity of the projectile and on the temperature, in which the arm is used. In this known arrangement however the adjustment can only be made in several steps.

An important deviation may also occur with angle shots, when the sighting line forms a more or less large angle with the horizontal line. With an arm ranged on 150 m. and its projectile having a muzzle velocity of 700 m./sec., the point of impact will deviate by 92 cm. with a shot of 75 under the horizontal line and a distance of 150 in. With these angle shots, uphill and downhill, the point of impact will deviate upwards. This defect is reduced with increasing muzzle velocity of the projectile. In order to avoid this deviation, already different sighting devices provided with a pendulum have been suggested. Said sighting devices are rather complicated and hardly allow the consideration of additional correcting values without larger expenditure. An essential disadvantage of sighting devices provided with a pendulum however is, that they are rather subject to jammings due to the accelerating forces occurring at the repulsion.

It further appeared that considerable target deviations may occur. when there are larger differences of sea level between the place, where the arm is ranged and that where it is used. These deviations are due to the reduced air resistance of the projectile at reduced atmospheric pressure and they amount to 16 cm. with a muzzle velocity of the projectile of 700 m./sec. and a distance of 250 m. at a sea level difference of 2,000 m., whereby the point of impact lies above the target. With high muzzle velocities of the projectile these deviations are reduced.

The last mentioned deviations naturally appear most intensively with the use of the arm in the mountains, whereby the two components of the deviations superpose each other additively. By listing the deviations in a table, this problem can only be solved most insufiiciently, since the arm must normally be ready foruse at once and there is no time left to find out in the table the adequate correcting values. With the conventional mechanical arrangements for the correction of the sighting line, it was difficult to take into account several correcting values, just because all of the correcting means hadto be arranged near or on the sight itself, respectively.

By the invention the disadvantages set forth above are avoided in that there is provided an electric comparator circuit, in which a current determined by a variable resistance controlled by the angle deviating means is comparable to a current determined by at least one resistance adjustable in dependence on the correcting values, whereby the output signal of the comparator circuit is fed to indicator means and/or control means, respectively. Such a comparator circuit need not implicitly be arranged with all of its parts in absolute vicinity of the sighting device or on it, respectively, but on the contrary it is possible to locate parts of the comparator circuit in the butt of the arm. Further, this circuit is much less sensible to accelerating forces. Hereto the indicator and/r control means show a semiconductor amplifier, whereby for instance bulbs or luminescence diodes are arranged in its output circult. These bulbs or the like flash up so long as the comparator circuit is unbalanced. that means so long as the sighting line is not correctly adjusted. A fully automatic correction is obtained, when according to an advanced embodiment of the invention, the control means are provided with a motor for changing the angle between the sighting line and the axis of the bore. This motor may be used for the deviation of the whole sighting telescope or for a displacement of a mark as well. According to an especially advanced embodiment of the invention, in which the angle inclination of the axis of the bore-in case also the tilting of the arm--is taken into account, a ring balance is provided, in which a resistance is disposed in a tube containing a drop of mercury, this in order to avoid the application of sensible mechanical parts.

Further advantages and features of the invention will become apparent from the following specification of an embodiment with reference to the drawing.

FIGS. la and lb illustrate schematically the conditions of an angle shot and of a shot on higher sea level.

FIG. 2 shows the inventive comparator circuit.

FIGS. 3 and 4 represent details in front elevation.

In FIG. la the tube of a hand firearm, for instance a gun, is marked by the number 1, which bears a sighting telescope 2. The sighting line of the sighting telescope is marked by the number 3, the axis of the bore of the tube 1 is marked by the number 4. The ballistic curve 5 of the projectile 6 intersects with a horizontal shot the sighting line 3 in the points A and B. With angle shots, not the total weight of the projectile G acts at right angle to the sighting line, but the component-G, while a second component G" causes an additional retardation of the projectile. Since the latter is not important with high muzzle velocities of the projectile and the usually occurring distances, thereresults a deviation of the point of impact by the distance a. Therefore, in order to reach with an angle shot the point B, it will be necessary to reduce the angle a between the sighting line and the axis of the bore by the amount Aa.

FIG. 1b illustrates the situation of a shot delivered on a relatively higher sea level, while the arm was ranged on a low sea level. Due to the reduced air resistance on higher sea levels, the point B will not be reached, but the point b" will be hit, which lies in a distance b above the target B. This deviation is also compensated by an adequate reduction of the angle a between the sighting line and the axis of the bore.

For taking into account different correcting values, the adjusting means for the sighting telescope 2 are connected with a variable resistance 7, as shown in FIG. 2. The variable resistance 7 is arranged in a Wheatstone bridge 8, which is fed by a battery 9. In further branches of this bridge there are disposed variable resistances 10, 11 for the consideration of further correcting values, as for instance the temperature or the muzzle velocity of the projectile. For taking into account the inclination of the bore axis of the tube 1, ringbalanceshaped means are provided in a branch of the bridge. Said means consist of a hollow torus 12, in which there is arranged a wire-wound resistance 13. On the one hand the wire-wound resistance 13, on the other hand the torus 12 is connected with the bridge, whereby the electric connection between the torus and the wire-wound resistance is established by a mercury drop 14. Depending on the angle position of the tube 1, the mercury drop thereby changes its position and therewith the active resistance. In the diagonal of the bridge 8 there is disposed a semiconductor amplifier 15, in the output circuit of which lie two bulbs 16,17.

Upon correct setting of the sighting line with respect to the axis of the bore, the bridge 8 is balanced, in the diagonal containing the amplifier 15 there flows no current and consequently the bulbs do not flash up. If the resistance 13 is displaced by the variation of the angle position of the tube 1, or the resistance 10 is displaced by the change of temperature, or the resistance 1 1 is displaced in consideration of another muzzle velocity of the projectile, respectively, the balance of the bridge 8 is disturbed. A current then flows in the diagonal branch of the bridge, which is amplified by the semiconductor amplifier 15, whereby, depending on the direction of the current, either the bulb 16 or the bulb l7 flashes up so long until the bridge 8 is correspondingly changed by the variation of the resistance 7 and therewith of the angle between the bore axis 4 and the sighting line 3.

In FIG. 3 an arrangement is illustrated, in which two different correcting values are taken into account in a single resistance 19. A lever is provided for considering the angle of inclination of the arm, which lever is pivotally arranged round a horizontal axis passing the sighting line at right angle. The lever 20 bears a weight 22 and is coupled with an attenuating cylinder 23. On said lever further acts a spring 24, which is adjusted thus, that upon horizontal setting of the sighting device, the lever 20 is likewise in a horizontal position. To the other end of the lever 20 there is connected a two-armed lever 25, the one end of which is coupled with bellows 26, which are displaceably arranged in vertical direction on a lead screw 27 for the scope of adjustment. The bellows 26 may be vertically displaced by twisting a screwed nut 28 propping to a stationary stop 29.

When the sighting device is horizontally adjusted and when the arm is on a sea level equal to that on which the arm and the sighting device were ranged, the lever 20 takes a horizontal position. The bellows 26 likewise cause a horizontal setting of the two-armed lever 25. When now the sighting device is inclined towards the horizontal line, only one component of the weight 22 acts on the sighting line at right angle, whereby the spring 24 deviates the lever 20 in clockwise sense. When the arm is still on the original sea level, the rear joint of the two-anned lever 25 takes its original position, so that the tap of the lever 25 is displaced downwards at the resistance 19 and the resistance 19 is set to a larger value. Upon use of the arm on another sea level, the bellows 26 cause a corresponding adjustment of the lever 25. Using the arm on a higher sea level and with larger inclination of the sighting line towards the horizontal line (angle shots), the tap of the lever 25 is deviated downwards according to the sum of the two correcting values.

According to an advanced embodiment of the invention, the output signal of the comparator circuit, which for instance may be designed as shown in FIG. 2, may be fed to a motor 30 (FIG. 4). According to the illustrated embodiment, this motor is connected with a swingable graduated dial 32. Said graduated dial 32 rests on the motor shaft 31 parallelly arranged to the sighting line 3. The graduated dial 32 is transparent and bears a curve 33. As shown in the embodiment, the motor 30 is formed by an electric indicating instrument. The vertical line of the graticule is marked in the drawing by the number 34. The intersection of the curve 33 with the vertical line 34 of the graticule determines the sighting line. In order to accommodate the sighting device to the different types of projectiles and therewith to the muzzle velocities and weights thereof, the dial 32 may be interchangeably arranged on the sighting device, whereby different curves 33 characterize the variable deviations of the particular types of ammunition with angle shots. When using this sighting device in sighting telescopes, it will be advantageous to arrange the graticule 34 in the first image plane of the telescope, the curve 33 in the second image plane thereof.

It is obvious that any number of correcting values is automatically or half automatically taken into account with the inventive sighting device. If, with half-automatic control, the setting of the sighting line to the bore axis does not correspond with the value resulting in consideration of the correcting value, the defective setting and in case also the necessary adjusting direction is indicated in the sight. The user has now to deviate the sighting line in the indicated sense so far towards the axis of the bore, until the indicating system signalizes the deviation 0, or with the application of bulbs, the bulb or both of them are extinguished. With fully automatic correction, this is done by the motor.

What is claimed is:

l. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, gravity dependent sensing means on said firearm for sensing its elevation angle, electric output producing means controlled by said gravity dependent sensing means and producing a second variable output in dependence on the elevation angle of the firearm, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said acute angle and the nominal value of said acute angle with respect to said at least one value causing a deviation, control means receiving said signals.

2. The sighting device, as set forth in claim I, wherein said control means comprises a motor means for varying said acute angle.

3. The sighting device, as set forth in claim 1, wherein said electric means are variable resistance means arranged within electric circuit means.

4. The sighting device, as set forth in claim 1, wherein said electric output producing means are variable resistance means arranged within electric circuit means.

5. The sighting device, as set forth in claim 1, wherein said computing means are electric comparator circuit means.

6. The sighting device, as set forth in claim 5, wherein said electric comparator circuit means are a Wheatstone bridge, and

said control means being arranged within one diagonal branch of said Wheatstone bridge.

7. The sighting device, as set forth in claim 1, wherein said control means comprise amplifier means.

8. The sighting device, as set forth in claim 1, wherein said control means comprise visual signal generating means.

9. The sighting device, as set forth in claim 2, further comprising telescopic sight means adjustably mounted on said firearm,

said means to vary said angle being adapted to adjust said telescopic sight means and being drivingly connected with said motor means.

10. The sighting device, as set forth in claim 2, further comprising telescopic sight means having sighting mark means defining said sighting line, at least one of said sighting marks means being adjustable to vary said acute angle, and

said motor means being drivingly connected with said adjustable sighting mark means.

11. The sighting device, as set forth in claim 10, wherein said sighting mark means comprise a dial pivotally arranged round an axis parallel to said sighting line, and

said dial bearing a curved mark.

12. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, temperature sensing means on said firearm, electric output producing means controlled by said temperature sensing means and producing a second variable output, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.

13. The sighting device, as set forth in claim 12, wherein said electric means are variable resistance means arranged within electric circuit means.

14. The sighting device, as set forth in claim 12, wherein said electric output producing means are variable resistance means arranged within electric circuit means.

15. The sighting device, as set forth in claim 12, wherein said computing means are electric comparator circuit means.

16. The sighting device, as set forth in claim 5, wherein said electric comparator circuit means are a Wheatstone bridge, and

said control means being arranged within one diagonal branch of said Wheatstone bridge.

17. The sighting device, as set forth in claim 12, wherein said control means comprise amplifier means.

18. The sighting device, as set forth in claim 12, wherein said control means comprise visual signal generating means.

19. The sighting device, as set forth in claim 12, wherein said control means comprises a motor means for varying said acute angle.

20. The sighting device, as set forth in claim 19, further comprising telescopic sight means adjustably mounted on said firearm,

said means to vary said angle being adapted to adjust said telescopic sight means and being drivingly connected with said motor means.

21. The sighting device, as set forth in claim 19, further comprising telescopic sight means having sighting mark means defining said sighting line, at least one of said sighting mark means being adjustable to vary said acute angle, and

said motor means being drivingly connected with said adjustable sighting mark means.

22. The sighting device, as set forth in claim 12, wherein said sighting mark means comprise a dial pivotally arranged round an axis parallel to said sighting line, and

said dial bearing a curved mark.

23. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, electric control means defining a second variable output in dependence on at least one value causing deviations of the point of impact from the target, said electric control means comprising: a resistance, an annular tube containing said resistance and having at least an inner conductive surface, circuit means electrically connected with one end of said resistance on the one hand and further connected with said inner conductive surface on the other hand, a drop of mercury displaceable within said annular tube and being adapted to connect said resistance with said conductive surface at various points, said annular tube being fixed on said firearm. computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.

24. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, electric control means defining a second variable output in dependence on at least one value causing deviations of the point of impact from the target, said electric control means comprising variable resistance means and air pressure gauge means, the latter controlling the variations of said variable resistance means, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.

25. A sighting device according to claim 24, wherein said air pressure gauge means are bellows. 

1. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, gravity dependent sensing means on said firearm for sensing its elevation angle, electric output producing means controlled by said gravity dependent sensing means and producing a second variable output in dependence on the elevation angle of the firearm, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said acute angle and the nominal value of said acute angle with respect to said at least one value causing a deviation, control means receiving said signals.
 2. The sighting device, as set forth in claim 1, wherein said control means comprises a motor means for varying said acute angle.
 3. The sighting device, as set forth in claim 1, wherein said electric means are variable resistance means arranged within electric circuit means.
 4. The sighting device, as set forth in claim 1, wherein said electric output producing means are variable resistance means arranged within electric circuit means.
 5. The sighting device, as set forth in claim 1, wherein said computing means are electric comparator circuit means.
 6. The sighting device, as set forth in claim 5, wherein said electric comparator circuit means are a Wheatstone bridge, and said control means being arranged within one diagonal branch of said Wheatstone bridge.
 7. The sighting device, as set forth in claim 1, wherein said control means comprise amplifier means.
 8. The sighting device, as set forth in claim 1, wherein said control means comprise visual sIgnal generating means.
 9. The sighting device, as set forth in claim 2, further comprising telescopic sight means adjustably mounted on said firearm, said means to vary said angle being adapted to adjust said telescopic sight means and being drivingly connected with said motor means.
 10. The sighting device, as set forth in claim 2, further comprising telescopic sight means having sighting mark means defining said sighting line, at least one of said sighting marks means being adjustable to vary said acute angle, and said motor means being drivingly connected with said adjustable sighting mark means.
 11. The sighting device, as set forth in claim 10, wherein said sighting mark means comprise a dial pivotally arranged round an axis parallel to said sighting line, and said dial bearing a curved mark.
 12. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, temperature sensing means on said firearm, electric output producing means controlled by said temperature sensing means and producing a second variable output, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.
 13. The sighting device, as set forth in claim 12, wherein said electric means are variable resistance means arranged within electric circuit means.
 14. The sighting device, as set forth in claim 12, wherein said electric output producing means are variable resistance means arranged within electric circuit means.
 15. The sighting device, as set forth in claim 12, wherein said computing means are electric comparator circuit means.
 16. The sighting device, as set forth in claim 5, wherein said electric comparator circuit means are a Wheatstone bridge, and said control means being arranged within one diagonal branch of said Wheatstone bridge.
 17. The sighting device, as set forth in claim 12, wherein said control means comprise amplifier means.
 18. The sighting device, as set forth in claim 12, wherein said control means comprise visual signal generating means.
 19. The sighting device, as set forth in claim 12, wherein said control means comprises a motor means for varying said acute angle.
 20. The sighting device, as set forth in claim 19, further comprising telescopic sight means adjustably mounted on said firearm, said means to vary said angle being adapted to adjust said telescopic sight means and being drivingly connected with said motor means.
 21. The sighting device, as set forth in claim 19, further comprising telescopic sight means having sighting mark means defining said sighting line, at least one of said sighting mark means being adjustable to vary said acute angle, and said motor means being drivingly connected with said adjustable sighting mark means.
 22. The sighting device, as set forth in claim 12, wherein said sighting mark means comprise a dial pivotally arranged round an axis parallel to said sighting line, and said dial bearing a curved mark.
 23. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, electric control means defining a second variable output in dependence on at least one value causing deviations of the point of impact from the target, said electric control means comprising: a resistance, an annular tuBe containing said resistance and having at least an inner conductive surface, circuit means electrically connected with one end of said resistance on the one hand and further connected with said inner conductive surface on the other hand, a drop of mercury displaceable within said annular tube and being adapted to connect said resistance with said conductive surface at various points, said annular tube being fixed on said firearm, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.
 24. A sighting device adapted for the use with firearms and defining a sighting line, an axis of bore of said firearm and said sighting line forming an acute angle, means adapted to vary said angle, electric means responsive to the value of said angle and defining a variable output in dependence on the value of said angle, electric control means defining a second variable output in dependence on at least one value causing deviations of the point of impact from the target, said electric control means comprising variable resistance means and air pressure gauge means, the latter controlling the variations of said variable resistance means, computing means receiving said two outputs and generating electric output signals upon divergences between the actual value of said angle and the nominal value of said angle with respect to said at least one value causing a deviation, control means receiving said signals.
 25. A sighting device according to claim 24, wherein said air pressure gauge means are bellows. 